Multiphase switching power converters (“multiphase converters”) comprise a plurality of switching power conversion phases that are controlled to operate in a parallel, interleaved, fashion, enabling delivery of high current at low output voltage with low output voltage ripple. In such converters, output voltage ripple may be reduced by closely matching the average phase currents; power density also improves with improved current sharing among phases because the phases may all be operated at, or close to, their maximum power rating without risk of inductor saturation.
Multiphase switching power converters and prior art apparatus and methods for enforcing current sharing among phases in multiphase converters are described in Abu-Qahouq et al, “Novel Control Method for Multiphase Low-Voltage High-Current Fast-Transient VRMs,” PESC 2002, Volume 4, pp. 1576-1581: Brooks et al, U.S. Pat. No. 6,285,571, Sep. 4, 2001, “Method and Apparatus for an Efficient Multiphase Switching Regulator”; Farrenkopf, U.S. Pat. No. 6,515,460, Feb. 4, 2003, “Multiphase Switching Regulator Control Architecture for Low On Time Systems that Enforces Current Sharing”; and in Yang and Guo, U.S. Pat. No. 6,404,175, Jun. 11, 2002, “Multi-Phase and Multi-Module Power Supplies With Balanced Current Between Phases and Modules.”